Substituted dihydro 3-halo-1H-pyrazole-5-carboxylates their preparation and use
View Patent ↗This invention relates to a compound of Formula I, a method for its preparation and its use in the preparation of a compound of Formula II wherein R 1 , R 2 , R 3 , X and n are as defined in the disclosure. This invention also discloses preparation of compounds of Formula III wherein R 1 , R 2 , R 6 , R 7 , R 8 and n are as defined in the disclosure. Also disclosed are certain intermediates of Formula 4 for the preparation of compounds of Formula I wherein X is N and R 2 , R 3 and n are as defined in the disclosure.
1. A compound of Formula 4
wherein
each R 2 is independently C 1 -C 4 alkyl, C 2 -C 4 alkenyl, C 2 -C 4 alkynyl, C 3 -C 6 cycloalkyl, C 1 -C 4 haloalkyl, C 2 -C 4 haloalkenyl, C 2 -C 4 haloalkynyl, C 3 -C 6 halocycloalkyl, halogen, CN, NO 2 , C 1 -C 4 alkoxy, C 1 -C 4 haloalkoxy, C 1 -C 4 alkylthio, C 1 -C 4 alkylsulfinyl, C 1 -C 4 alkylsulfonyl, C 1 -C 4 alkylamino, C 2 -C 8 dialkylamino, C 3 -C 6 cycloalkylamino, C 3 -C 6 (alkyl)cycloalkylamino, C 2 -C 4 alkylcarbonyl, C 2 -C 6 alkoxycarbonyl, C 2 -C 6 alkylaminocarbonyl, C 3 -C 8 dialkylaminocarbonyl or C 3 -C 6 trialkylsilyl;
X is N;
R 3 is H or C 1 -C 4 alkyl; and
n is 0 to 3.
2. A compound of claim 1 wherein n is 1 to 3.
3. A compound of claim 1 wherein each R 2 is independently Cl or Br, and one R 2 is at the 3-position.
4. A compound of claim 1 wherein a is 1 ; R 2 is Cl and is at the 3-position; and R 3 is ethyl.